An endoprosthesis may be configured to be positioned in a body lumen for a variety of medical applications. For example, an endoprosthesis may be used to treat a stenosis in a blood vessel, used to maintain a fluid opening or pathway in the vascular, urinary, biliary, tracheobronchial, esophageal or renal tracts, or to position a device such as an artificial valve or filter within a body lumen, in some instances. In some instances, an endoprosthesis may be used within an organ such as the pancreas, in the biliary system or in the pulmonary system. In some cases, there can be a desire to retain patency within a main lumen while not blocking fluid flow from side branches feeding into or out of the main lumen. In some cases, there can be a desire to provide endoprostheses that exhibit anti-migration features, while reducing the trauma to the body lumen of the patient if removal of the endoprosthesis is desired. In some cases, there can be a desire to avoid tissue irritation that can occur in response to a bare metal stent or stent component contacting tissue.
Accordingly, it is desirable to provide endoprostheses that can retain patency within a main lumen within the body structure while not blocking fluid flow from side branches within the body structure, while providing anti-migration features, and/or while avoiding tissue irritation.